crypto: mv_cesa - Use IPAD/OPAD constant

This patch simply replace all occurrence of HMAC IPAD/OPAD value by their
define.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/mv_cesa.c

@@ -18,6 +18,7 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/clk.h>
+#include <crypto/hmac.h>
 #include <crypto/internal/hash.h>
 #include <crypto/sha.h>
 #include <linux/of.h>
@@ -822,8 +823,8 @@ static int mv_hash_setkey(struct crypto_ahash *tfm, const u8 * key,
 		memcpy(opad, ipad, bs);
 
 		for (i = 0; i < bs; i++) {
-			ipad[i] ^= 0x36;
-			opad[i] ^= 0x5c;
+			ipad[i] ^= HMAC_IPAD_VALUE;
+			opad[i] ^= HMAC_OPAD_VALUE;
 		}
 
 		rc = crypto_shash_init(shash) ? :